1. Field of the Invention
The present invention relates to a hoist system for hoisting heavy objects; and, more particularly to a system for hoisting a flat screen television or a heavy mirror or picture within a room wherein the flat screen television or heavy object is brought into close proximity of the room wall, enabling its attachment to wall brackets and the like by a single person.
2. Description of the Prior Art
Many patents address issues related to lifting heavy weights in an industrial environment using fork lift trucks. In these devices, the heavy weight of the truck balances the weight of the object being lifted and the weight of the object lifted is inherently less that that of the weight of the fork lift truck body Several prior art patents address lifting mechanisms for televisions; but the devices disclosed by these patents are either already attached to a wall or place the television too far away from the wall. Consequently, in use of such devices, a flat screen television could not be readily hung on a wall by a single person.
U.S. Pat. No. 1,126,368 to Boensch et al. discloses a warehouse truck for handling rolls of paper. A hinged arm is lowered or raised by pulling on a flexible cable. Since the arm swings in a circular motion, its distance from, for example, a stationary wall changes as a function of height lifted, preventing an object from being brought into close proximity with a vertical wall. The weight is not lifted in a vertical plane. This light weight handling device is designed for lifting rolls of paper, not heavy weights.
U.S. Pat. No. 2,250,577 to Ernst discloses a container handling device for handling heavy barrels, bails and the like. A fork engages the bottom of a drum. The top of the drum is engaged by a gripping mechanism, and the drum is tiled and lifted above ground level to effect transport thereof. Since the object to be lifted is tilted, it is not lifted vertically.
U.S. Pat. No. 2,539,233 to Dickson discloses a lift truck and attachment therefor. Like the device taught by the '577 patent, a fork engages the bottom of a drum. The top of the drum is engaged by a gripping mechanism, and the drum is tiled when lifted above ground level to transport the drum. Since the object to be lifted is tilted, it is not lifted vertically.
U.S. Pat. No. 2,620,932 to Alpine discloses a kiln truck. This kiln truck is slid into the bottom of a kiln. An elevator frame is slid under ceramic ware within the kiln, and is lifted by a hydraulic cylinder. The purpose of this lifting is only to raise the ceramic ware off the floor of the kiln; and the load is not lifted to a substantial height. Since the front wheels kiln truck extend beyond the lifted load, the load cannot be brought close to a wall.
U.S. Pat. No. 2,807,382 to Schenkelberger discloses an industrial lift truck with a load clamp. The load is clamped by a plurality of telescoping means. The industrial fork lift is not well suited for use within the interior of a residential dwelling. The weight of the truck is used to balance the lifted load. Consequently, the load lifted must be significantly lower than the weight of the truck.
U.S. Pat. No. 2,827,184 to Mueller discloses a drum handling attachment for a fork lift. The attachment is designed solely to handle cylindrical containers. The lifting device relies on the attachment of the two tubes to be fitted into a fork lift, which constitutes heavy machinery unsuitable for use in a residential dwelling.
U.S. Pat. No. 3,199,699 to Dayton discloses a load carrying mechanism for a lift truck. A shift frame is supported on an elevating structure of a vehicle. Pivotally supported on the shift frame is a pivot frame, which provides support on the vertical axis pivot means for lateral pivotal movement. The pivot frame carries a plurality of load-engaging clamps. A lifting mechanism is mounted on the front of the truck. The weight of the load carried is balanced by the weight of the truck. The lift mechanism is not suited for lifting a flat screen television or heavy load within a residential dwelling.
U.S. Pat. No. 3,455,476 to Grigsby discloses an attachment for a lift truck. This attachment is adapted for handling crates of glass even when the crates rest directly on the floor surface against a wall or are stacked against each other. A load engaging foot is mounted on the lower end of the truck, and a telescoping clamping arm reciprocapable on a mask clamps the load. Movement of the foot member beneath the load is made possible by the relative sliding movement of the inner claw with respect to the support arm. The outer claw is engaged and the load is shifted rearwardly to a position above the front wheels of the truck. An attachment on the truck has a mast with a bottom support. A load clamping arm is used to secure and lift the load. The attachment is fixed to the truck. A bottom support and a movable arm of the attachment clamp the load. The clamped load is then lifted. Clearly, this heavy industrial weight truck is not well suited for use in a residential dwelling.
U.S. Pat. No. 4,025,017 to Miller discloses a wall mounted lift for a television receiver or the like. A spring-loaded hoist mountable vertically on a wall is provided for use particularly in mounting a heavy television receiver to a wall and raising it to an elevated position. The hoist includes a fixed housing, which is attached permanently to the vertical wall of a room and is formed with a vertical guide channel. A movable carriage is mounted within the housing for vertical reciprocation along the guide channel and is urged upwardly by means of a constant force spring reel assembly mounted in the top of the housing and connected to the carriage. The carriage includes a locking mechanism adapted to engage the housing for locking the carriage in a lowered position and also includes a connecting member adapted to engage a cooperating connecting member of a television by means of which the carriage, when unlocked and supporting a television, may be raised or lowered with little physical effort. This wall mounted lift has an elongated housing that is screwed or bolted to the wall and carries a movable carriage. A television receiver is reeled to the movable carriage using a cart. When the cart is in its lowest position, the television receiver is secured to the movable carriage by lockable pins. The housing is permanently present on the wall and is unsightly. The television is not lifted to or attached to a fixed or a swinging wall bracket.
U.S. Pat. No. 4,285,626 to Donato discloses a fork lift truck with plate glass handling attachment. A fork lift truck is equipped with an attachment or fixture for handling a plate glass load. The truck is also equipped with a control system, which includes a sensing switch for automatically controlling the operation of the truck. The control system also includes a release switch for preventing the truck from backing up, following deposit of a plate glass item at a storage area, until the plate glass load fixture has cleared the plate glass item. This glass plate lifting attachment is secured to a truck and carries glass in a slightly inclined orientation. It does not suggest or disclose a mechanism for lifting a flat screen television or heavy weight with a room of a house.
U.S. Pat. No. 4,394,106 to Frees et al. discloses a glass handling lift truck. A lift truck mechanism handles glass sheets having a glass pack lifting frame. Gripping devices at the sides of the lifting frame engage sides of a glass pack. Feet at the bottom of the lifting frame support the glass pack on the frame. A framework of the mechanism attaches it to the lift mast of the lift truck. An operator control station platform extends rearwardly from the lifting frame above the lift mast. An intermediate frame is carried by the framework in selectively extendable relationship in front of the mast. A first pair of swinging frames is swingably affixed to the intermediate frame for swinging movement on an upright axes at the opposite sides of the intermediate frame. A second pair of swinging frames is swingably affixed at proximal ends to the distal ends of the first pair of frames. Distal ends of the second pair of frames are pivoted to the lifting frame. A drag link interconnects the distal ends of the first pair of frames. First and second sets of hydraulic cylinders, respectively, effect side-shifting and slewing movements of the lifting frame relative to the lift truck. A front portion of the truck designed for handling glass sheets in a nearly vertical orientation, protects the driver of the truck from damage due to glass breakage. This heavy equipment is not well suited for use in a residential dwelling or a confined space.
U.S. Pat. No. 4,881,866 to Harmon discloses a glass handling apparatus. A sheet handling apparatus is adapted for attachment to a fork lift truck to transport stacks of vertically disposed sheet material from one location to another. The apparatus includes a frame adapted for attachment to the forks of a fork lift truck and a lower support for supporting the lower edges of the sheets. The lower support is adjustably connected to the frame, permitting vertical adjustment of the lower support relative to the frame. The apparatus also includes an upper support pivotally mounted on the frame for engaging the back side of the stack during transport. This glass lifting apparatus is attached to a fork lift truck. It is bulky and cannot be used in a room or confined space. No means are provided to prevent tipping of the lifted load.
U.S. Pat. No. 4,902,187 to Rousseau discloses a drum dolly attachment apparatus. A conventional dolly truck assembly has a drum attachment assembly connected thereto. The drum attachment assembly is slidably mounted on an upright vertical handle of the dolly truck assembly. It is in contact with and grasps a main rim portion of the drum member. The drum attachment assembly is constructed so as to move vertically as required to adjust its position on the main rim portion of the drum member, when moved from a vertical to an inclined position. The drum attachment assembly includes a drum connector assembly having a first stationary drum connector connectable to an upper inner portion of the main rim portion and a second actuator drum connector connectable to an outer lower portion of the main rim portion of the drum member. The actuator drum connector is movable against a bias member to a released position and vertically on the support tube of the dolly truck assembly for use in attaching to another drum member for a subsequent grasping, moving, and transporting operation. This drum dolly is mounted on wheels and grabs a drum which can be tilted for transportation. The device disclosed by the '187 patent does not lift the drum. It is not designed to grab anything other than a cylindrical drum. Accordingly, there is no disclosure or suggestion in the '187 patent concerning a hoisting device for hoisting a flat screen television in a room.
U.S. Pat. No. 5,122,027 to Tabayashi discloses a carrier for a container. A carrier comprises a lift bar provided on the body of the carrier and movable upward and downward, a connecting member pivotably connected between an upwardly driving cylinder device and the lift bar, an upper claw provided on the connecting member, and a lower claw provided on the lift bar and cooperative with the upper claw for holding the upper rim of a container. The load of the container acting on the lower claw pulls down the upper claw for the two claws to clamp the container upper rim to transport the container as lifted. This is a hand truck for lifting a cylinder from the ground for its transportation. The drum is not lifted to any height. Since the drum is outside the wheel base it is subject to tipping. The weight of the heavy drum must be carried by the operator using the handle.
U.S. Pat. No. 5,184,934 to Gallo discloses a gripping device and method of use. A gripping device is used in combination with a front-end loader for lifting and transporting heavy objects. The device comprises a slot-entering jaw means, a second jaw means, a jaw adjusting means to effect movement of one of said slot-entering jaw means and said second jaw means relative to other of said jaw means, and a loader cooperation means by which said device is adapted to cooperate with the loader. The device is particularly useful for removing slabs of concrete from a pre-cut concrete floor, such as found in multi-storey parking garages, during demolition or rehabilitation. This gripping device is attached to a truck and all the lifting is done by the truck. Therefore the gripping device does not suggest a hoisting device for positioning flat screen televisions within the confines of a room.
U.S. Pat. No. 5,501,497 to Holloway discloses an adjustable drum handling carrier. The adjustable drum handling carrier is particularly adapted for use in handling fiber drums. It includes an upright tube with a telescoping top and bottom bracket tubes. The upright tube is attached to a midpoint of a cradle. The side wall of the drum is peripherally engaged by the cradle, and the ends of the drum are engaged by the top and bottom brackets. This drum carrier is removably attached to a drum and has to be lifted by a separate lifting device, the nature of which is not disclosed.
U.S. Pat. No. 5,509,774 to Yoo discloses a load clamping apparatus with an increased extend of vertical movement. A load clamping apparatus is provided for use with a forklift truck including a mast having a vertical guide channel, a lift carriage mounted to the mast for elevational movement there along and a pair of spaced apart forks carried by the lift carriage to support a load to be handled. The load clamping apparatus comprises: a slider member slidably fitted into the vertical guide channel and elevationally movable along the mast, the slider member having a vertical guide groove; a clamp carriage slidably fitted into the vertical guide groove of the slidable member for pressing the load against the pair of spaced apart forks; an actuator pivotally affixed to the mast for causing the slider member to move up and down; upper and lower rotary guide rollers each rotatably mounted to top and bottom ends of the slider member; a first pliable connector having a first end anchored to the mast and a second end fixedly secured to the clamp carriage, the first pliable connector extending upwardly from the first end thereof, turning around the upper rotary guide rollers and then extending downwardly to reach the second end thereof; and a second pliable connector having a first end anchored to the mast and a second end fixedly secured to the clamp carriage, the second pliable connector extending downwardly from the first end thereof, turning around the lower rotary guide rollers and then extending upwardly to reach the second end thereof. This is a fork lift truck with two widely spaced tines and a top clamp plate designed to lift heavy objects. The weight of the heavy object is countered by the weight of the fork lift truck and therefore, its weight is less than or equal to the weight of the fork lift truck. This fork lift truck is not suitable for use in a room to lift a flat screen television to a suitable height.
US Patent Application No. 2005/0045077 to Bober discloses a motorized lift device for facilitating the uninterrupted and nearly noiseless movement of a low-profile television. The motorized lift comprises a base unit having a support unit slidably disposed thereon in a vertically-oriented and telescoping fashion. Support unit movement is controlled via a motor directly coupled to a transmission, which is coupled to a screw. Coupling between screw and an elevator plate converts screw rotation to linear motion within the support unit. A low-friction floating nut between elevator plate and screw, as well as several low-friction couplings between the base unit and the support unit reduce noise and wobbling, eliminate binding, and accommodate for misalignments during movement. The support unit accommodates for vertical and horizontal adjustability during mounting and installation of any size low-profile television. The motorized lift device is not on wheels and cannot be readily moved about. The base of the unit is above ground and cannot reach a heavy flat screen television that is placed on the ground. The base unit protrudes and therefore cannot place a hoisted flat screen television close to a wall.
There remains a need in the art for a hoisting device that would enable a single person to position a flat screen television or other heavy object such as a mirror, large frame picture and the like, reliably on the wall of a room of a residential dwelling.